When seated for extended periods of time, such as occurs when riding or driving long distances, or operating heavy equipment such as a bulldozer or tractor, the posterior area is subjected to prolonged compression which often results in general discomfort, numbness and even pain. The discomfort and pain is often exacerbated by the constant vibration and repetitive bouncing which often accompanies long distance travel and operation of heavy equipment.
It is a common practice for persons suffering such effects to stop traveling or working and get out of the vehicle or equipment in order to stand, stretch and/or walk. While effective for relieving the discomfort, numbness and/or pain, such relief is only temporary and repetitive stops are undesired and unpractical.
U.S. Pat. Nos. 4,175,297, 5,103,518, 5,109,560, 5,500,965, 5,839,140, 5, 963,997, 6,014,784, 6,216,299 and 6,668,405 disclose wheelchair cushion systems wherein the cushion includes an array of inflatable cells including first and second interconnected groupings of cells interspersed throughout the array which are alternately inflated and deflated on a predetermined schedule in order to vary the location of contact between the cushion and the posterior of a person seated on the cushion. Inflation and deflation of the cell groups are linked so that inflation of one group of cells automatically causes deflation of the other group of cells.
While effective for reducing the development of discomfort, numbness and pain when seated for extended periods, such cushions are expensive, noisy and not well suited for use in environments with limited room, such as the driver's side area of an automobile or a motorcycle. Hence, a continuing need exists for a low-cost, quiet, compact inflatable cushion capable of reducing or eliminating the discomfort, numbness and pain which can accompany prolonged seating.